Should we rename the MASTER forest?

[Mark Reinhold]

> Date: Thu, 08 Nov 2007 19:53:21 +0000
> From: Andrew John Hughes <gnu_andrew at member.fsf.org>

> jdk7 seems a bit odd, given that presumably the mercurial repositories will
> live on beyond the release of version 7.  How about simply jdk?  Or am I
> missing some subtle point that means we can't simply mark a snapshot that
> was the jdk7 release?

Good question!

Yes, we could tag the final changeset in each tree, but ...

Our usual practice has been to freeze the master TeamWare workspaces for
each release when that release goes final.  Successor releases, whether
they're small update releases or the next big feature release, are
developed in their own workspaces, which start out as clones of the
original master.  This is, yes, different from the way that people tend
to use centralized SCMs such as CVS and Subversion.

Transposing this to Mercurial: When JDK 7 ships then the jdk7 master
forest will be archived, and work on JDK 8 will begin in a jdk8 forest,
which will initially be a clone of jdk7.

One could argue that this practice arose in response to the inherent
weaknesses of TeamWare, and that's largely true.  There are, however,
at least two reasons to retain it:

  - Familiarity - This counts for a lot.  We're already forcibly
    stretching the brains of Sun engineers to transition from TeamWare
    to Mercurial; let's not stretch them more than absolutely needed.

  - Paranoia - So far Mercurial has been very robust in our experience,
    but there is nonetheless a certain comfort in knowing that a
    read-only, archived copy of every release forest is readily available
    just in case something goes very wrong.  (Yes, of course we do
    backups too, but restoring really old backups tends to be painful.)

None of this is cast in stone.  If down the road we find better reasons
to have just one big JDK master forest then we can pretty easily make
that happen.

To be clear, the URL for the JDK 7 master forests is currently

    http://hg.openjdk.java.net/jdk7/MASTER

but with my proposal will change to

    http://hg.openjdk.java.net/jdk7/jdk7

and live alongside the other JDK 7 integration forests:

    http://hg.openjdk.java.net/jdk7/2d
    http://hg.openjdk.java.net/jdk7/awt
    http://hg.openjdk.java.net/jdk7/build
    http://hg.openjdk.java.net/jdk7/corba
    http://hg.openjdk.java.net/jdk7/hotspot
    http://hg.openjdk.java.net/jdk7/...

- Mark